Вот мой код сервлета
@MultipartConfig(maxFileSize = 16177215)
// upload file's size up to 16MB
public class UploadServlet extends HttpServlet {
// database connection settings
// private String dbURL = "jdbc:postgresql://localhost:5432/postgres";
// private String dbUser = "postgres";
// private String dbPass = "magerna";
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
// gets values of text fields
String firstName = request.getParameter("firstName");
String lastName = request.getParameter("lastName");
InputStream inputStream = null; // input stream of the upload file
// obtains the upload file part in this multipart request
Part filePart = request.getPart("photo");
if (filePart != null) {
// prints out some information for debugging
System.out.println(filePart.getName());
System.out.println(filePart.getSize());
System.out.println(filePart.getContentType());
// obtains input stream of the upload file
inputStream = filePart.getInputStream();
}
Connection conn = null; // connection to the database
String message = null; // message will be sent back to client
try {
// connects to the database
Class.forName("org.postgresql.Driver");
conn = DriverManager.getConnection(
"jdbc:postgresql://localhost:5432/postgres", "postgres",
"magerna");
// constructs SQL statement
String sql = "INSERT INTO test.contacts (first_name, last_name, photo) values (?, ?, ?)";
PreparedStatement statement = conn.prepareStatement(sql);
statement.setString(1, firstName);
statement.setString(2, lastName);
if (inputStream != null) {
// fetches input stream of the upload file for the blob column
statement.setBinaryStream(3, inputStream);
}
int row = statement.executeUpdate();
if (row > 0) {
message = "File uploaded and saved into database";
}
} catch (Exception ex) {
message = "ERROR: " + ex.getMessage();
ex.printStackTrace();
} finally {
if (conn != null) {
// closes the database connection
try {
conn.close();
} catch (SQLException ex) {
ex.printStackTrace();
}
}
// sets the message in request scope
request.setAttribute("Message", message);
// forwards to the message page
request.getRequestDispatcher("/Message.jsp").forward(request, response);
}
}
}
Вот мой код jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>File Upload to Database Demo</title>
</head>
<body>
<center>
<h1>File Upload to Postgre Database </h1>
<form method="post" action="UploadServlet" enctype="multipart/form-data">
<table border="0">
<tr>
<td>First Name: </td>
<td><input type="text" name="firstName" size="50"/></td>
</tr>
<tr>
<td>Last Name: </td>
<td><input type="text" name="lastName" size="50"/></td>
</tr>
<tr>
<td>Photo: </td>
<td><input type="file" name="photo" size="50"/></td>
</tr>
<tr>
<td colspan="2">
<input type="submit" value="Save">
</td>
</tr>
</table>
</form>
</center>
</body>
</html>
Я использую PostgreSQL для добавления значения в БД.Я использую Bytea тип данных для хранения файла изображения вместо BLOB.Изображение загружается в таблицу базы данных, я хочу отобразить изображение на той же странице Upload.jsp после загрузки.
Может кто-нибудь обновить мой код сервлета или подсказать мне возможное решение?Заранее спасибо.